Microbiological and molecular profile of furcation defects in a population with untreated periodontitis.

AIM: To describe the microbiological composition of subgingival dental plaque and molecular profile of gingival crevicular fluid (GCF) of periodontal furcation-involved defects. MATERIALS AND METHODS: Fifty-seven participants with periodontitis contributed with a degree II-III furcation involvement (FI), a non-furcation (NF) periodontal defect and a periodontally healthy site (HS). Subgingival plaque was analysed by sequencing the V3-V4 region of the 16S rRNA gene, and a multiplex bead immunoassay was carried out to estimate the GCF levels of 18 GCF biomarkers. Aiming to explore inherent patterns and the intrinsic structure of data, an AI-clustering method was also applied. RESULTS: In total, 171 subgingival plaque and 84 GCF samples were analysed. Four microbiome clusters were identified and associated with FI, NF and HS. A reduced aerobic microbiota (p = .01) was detected in FI compared with NF; IL-6, MMP-3, MMP-8, BMP-2, SOST, EGF and TIMP-1 levels were increased in the GCF of FI compared with NF. CONCLUSIONS: This is the first study to profile periodontal furcation defects from a microbiological and inflammatory standpoint using conventional and AI-based analyses. A reduced aerobic microbial biofilm and an increase of several inflammatory, connective tissue degradation and repair markers were detected compared with other periodontal defects.

"Determining the efficacy of a machine learning model for measuring periodontal bone loss".

BACKGROUND: Considering the prevalence of Periodontitis, new tools to help improve its diagnostic workflow could be beneficial. Machine Learning (ML) models have already been used in dentistry to automate radiographic analysis. AIMS: To determine the efficacy of an ML model for automatically measuring Periodontal Bone Loss (PBL) in panoramic radiographs by comparing it to dentists. METHODS: A dataset of 2010 images with and without PBL was segmented using Label Studio. The dataset was split into n = 1970 images for building a training dataset and n = 40 images for building a testing dataset. We propose a model composed of three components. Firstly, statistical inference techniques find probability functions that best describe the segmented dataset. Secondly, Convolutional Neural Networks extract visual information from the training dataset. Thirdly, an algorithm calculates PBL as a percentage and classifies it in stages. Afterwards, a standardized test compared the model to two radiologists, two periodontists and one general dentist. The test was built using the testing dataset, 40 questions long, done in controlled conditions, with radiologists considered as ground truth. Presence or absence, percentage, and stage of PBL were asked, and time to answer the test was measured in seconds. Diagnostic indices, performance metrics and performance averages were calculated for each participant. RESULTS: The model had an acceptable performance for diagnosing light to moderate PBL (weighted sensitivity 0.23, weighted F1-score 0.29) and was able to achieve real-time diagnosis. However, it proved incapable of diagnosing severe PBL (sensitivity, precision, and F1-score = 0). CONCLUSIONS: We propose a Machine Learning model that automates the diagnosis of Periodontal Bone Loss in panoramic radiographs with acceptable performance.

The efficiency of two different synthetic bone graft materials on alveolar ridge preservation after tooth extraction: a split-mouth study.

BACKGROUND: Alveolar Bone loss occurs frequently during the first six months after tooth extraction. Various studies have proposed different methods to reduce as much as possible the atrophy of the alveolar ridge after tooth extraction. Filling the socket with biomaterials after extraction can reduce the resorption of the alveolar ridge. We compared the height of the alveolar process at the mesial and distal aspects of the extraction site and the resorption rate was calculated after the application of HA/ß-TCP or synthetic co-polymer polyglycolic - polylactic acid PLGA mixed with blood to prevent socket resorption immediately and after tooth extraction. METHODS: The study was conducted on 24 extraction sockets of impacted mandibular third molars bilaterally, vertically, and completely covered, with a thin bony layer. HA/ß-TCP was inserted into 12 of the dental sockets immediately after extraction, and the synthetic polymer PLGA was inserted into 12 of the dental sockets. All sockets were covered completely with a full-thickness envelope flap. Follow-up was performed for one year after extraction, using radiographs and stents for the vertical alveolar ridge measurements. RESULTS: The mean resorption rate in the HA/ß-TCP and PLGA groups was ± 1.23 mm and ± 0.1 mm, respectively. A minimal alveolar bone height reduction of HA/ß-TCP was observed after 9 months, the reduction showed a slight decrease to 0.93 mm, while this rate was 0.04 mm after 9 months in the PLGA group. Moreover, the bone height was maintained after three months, indicating a good HA/ß-TCP graft performance in preserving alveolar bone (1.04 mm) while this rate was (0.04 mm) for PLGA. CONCLUSION: The PLGA graft demonstrated adequate safety and efficacy in dental socket preservation following tooth extraction. However, HA/ß-TCP causes greater resorption at augmented sites than PLGA, which clinicians should consider during treatment planning.

SGK1 negatively regulates inflammatory immune responses and protects against alveolar bone loss through modulation of TRAF3 activity.

Serum- and glucocorticoid-regulated kinase 1 (SGK1) is a serine/threonine kinase that plays important roles in the cellular stress response. While SGK1 has been reported to restrain inflammatory immune responses, the molecular mechanisms involved remain elusive, especially in oral bacteria-induced inflammatory milieu. Here, we found that SGK1 curtails Porphyromonas gingivalis-induced inflammatory responses through maintaining levels of tumor necrosis factor receptor-associated factor (TRAF) 3, thereby suppressing NF-κB signaling. Specifically, SGK1 inhibition significantly enhances production of proinflammatory cytokines, including tumor necrosis factor α, interleukin (IL)-6, IL-1ß, and IL-8 in P. gingivalis-stimulated innate immune cells. The results were confirmed with siRNA and LysM-Cre-mediated SGK1 KO mice. Moreover, SGK1 deletion robustly increased NF-κB activity and c-Jun expression but failed to alter the activation of mitogen-activated protein kinase signaling pathways. Further mechanistic data revealed that SGK1 deletion elevates TRAF2 phosphorylation, leading to TRAF3 degradation in a proteasome-dependent manner. Importantly, siRNA-mediated traf3 silencing or c-Jun overexpression mimics the effect of SGK1 inhibition on P. gingivalis-induced inflammatory cytokines and NF-κB activation. In addition, using a P. gingivalis infection-induced periodontal bone loss model, we found that SGK1 inhibition modulates TRAF3 and c-Jun expression, aggravates inflammatory responses in gingival tissues, and exacerbates alveolar bone loss. Altogether, we demonstrated for the first time that SGK1 acts as a rheostat to limit P. gingivalis-induced inflammatory immune responses and mapped out a novel SGK1-TRAF2/3-c-Jun-NF-κB signaling axis. These findings provide novel insights into the anti-inflammatory molecular mechanisms of SGK1 and suggest novel interventional targets to inflammatory diseases relevant beyond the oral cavity.

Molecular profiling of gingival crevicular fluid fails to distinguish between infrabony and suprabony periodontal defects.

AIM: To assess the differential molecular profiling of gingival crevicular fluid (GCF) from infrabony and suprabony periodontal defects compared with healthy sites. MATERIALS AND METHODS: Seventy-five samples from 25 patients with untreated periodontitis stage III-IV were included. Clinical and radiological parameters as well as GCF samples were collected from an infrabony defect, a suprabony defect and a periodontally healthy site per patient. A multiplex bead immunoassay was performed to assess the level of 18 biomarkers associated with inflammation, connective tissue degradation and regeneration/repair. RESULTS: GCF volume was higher in periodontal sites compared with healthy sites, with no significant difference between infrabony and suprabony defects. Fourteen biomarkers were elevated in infrabony and suprabony sites compared with healthy sites (p < .05). Only interleukin-1α levels were increased in infrabony compared with suprabony sites, whereas there was no difference in probing pocket depth. CONCLUSIONS: Although the GCF molecular profile clearly differentiates periodontally affected sites from healthy sites, the different architecture between infrabony and suprabony defects is not reflected in GCF biomarker changes.

Clinical efficacy of hyaluronic acid in the treatment of periodontal intrabony defect: a systematic review and meta-analysis.

OBJECTIVE: This systematic review aimed to evaluate the effects of hyaluronic acid (HA) alone or in combination with any bone substitute for the treatment of intrabony defects (IBDs). MATERIAL AND METHODS: Six databases were searched up to April 2022 to find randomized clinical trials comparing the clinical effects of open flap debridement (OFD) + HA versus OFD alone (first group) or OFD + HA + bone substitutes versus OFD + bone substitutes (second group) in the treatment of IBDs with a follow-up of at least 3 months. Random effects models of mean differences were used to determine the clinical attachment level (CAL) gain, probing depth (PD) reduction, and radiographic bone fill (RBF). RESULTS: Of the 276 studies identified, 6 were included in the qualitative synthesis, and 5 in the meta-analyses. The meta-analyses in the first group showed a statistically significant differences for CAL gain (mean difference [MD]:1.00; 95% confidence interval [CI]:0.65 - 1.35; n = 2) and PD reduction (MD: 0.76; 95%CI: 0.34 - 1.17; n = 2) favoring HA + OFD at 6 months. However, in the second group, the meta-analyses did no show additional effect of HA in association with bone substitute was demonstrated for either CAL gain (MD: 0.57; 95%CI: - 0.30 - 1.43; n = 2) or PD reduction (MD: 1.05; 95%CI: - 0.38 - 2.47; n = 2) but did show significant differences for RBF (MD: 0.57; 95%CI: 0.15 - 0.99; n = 2) at 12 months. CONCLUSION: Compared with OFD alone, local application of HA in the treatment of IBDs provided a significant CAL gain and PD reduction at 6 months. However, its combination with bone substitutes showed no statistically significant differences at 12 months. CLINICAL RELEVANCE: The use of OFD + HA improves the CAL and PD in the treatment of IBDs compared to OFD only after 6 months of follow-up. These results are not maintained after 12 months.

Cone-beam-computed tomography evaluation of mandibular nutrient canals in patients with periodontal diseases.

Background and Aim: The aim of this study was to evaluate radiographically the prevalence of mandibular nutrient canals (NCs) in patients with/without periodontal bone loss with aging and to correlate the number of NCs with the severity of bone loss using cone-beam-computed tomography (CBCT). Patients and Methods: CBCT examinations of 208 patients were evaluated retrospectively of all patients, 114 had periodontal bone loss, whereas 94 patients were control subjects. Alveolar bone loss investigations were performed according to the Progressive Rate Index. Results: NCs were observed in 55% of the control group and 86% of the periodontitis patients. NCs were more prevalent in the elderly age group with periodontal bone loss. In the study group, the NCs were statistically more frequent than in the control subjects (P > 0.05). Conclusion: Statistical analysis showed a significant difference between the age groups and the prevalence of NCs increased in patients with periodontal alveolar bone loss with aging (P < 0.05).

Iron accumulation is associated with periodontal destruction in a mouse model of HFE-related haemochromatosis.

OBJECTIVE: To investigate the effect of Hfe gene mutation on the distribution of iron and periodontal bone loss in periodontal tissues. BACKGROUND DATA: It remains unclear how tissue iron loading affects the periodontium architectures in a genetic animal model of hereditary haemochromatosis (HH). METHODS: Male C57BL/6 Hfe -/- (8 weeks old) and wild-type (WT) mice were utilized to examine the iron distribution in periodontal tissues, as well as periodontal tissues changes using micro-computed tomography and histomorphometric analysis. Furthermore, tissue inflammatory mediators, bone markers and periodontal pathogens were carried out in PFA-fixed paraffin-embedded tissues using ELISA, RT-qPCR and genomic DNA qPCR, respectively. RESULTS: Excessive iron deposition was found in the periodontal ligament, gingiva and alveolar bone in Hfe -/- mice relative to their WT counterparts. This, in turn, was associated with significant periodontal bone loss, increased cemento-enamel junction-alveolar bone crest distance and decreased expression of molecules involved in bone development and turnover. Furthermore, the pro-inflammatory cytokine - interleukin 6 and periodontal bacteria - Campylobacter rectus were significantly increased in Hfe -/- mice compared with WT controls. CONCLUSION: Our results suggest that the iron loading in a mouse model of HH decreases alveolar bone formation and leads to alterations in the inflammatory state in the periodontium. Periodontal health should be assessed during the clinical assessment of HFE-HH patients.

Radiographic Detection of the Relationship between Tonsilloliths and Dental Plaque-Related Pathologies in a Series of Digital Panoramic Radiographs.

OBJECTIVE: The purpose of this study was to analyse the prevalence of tonsilloliths and to determine radiographically whether there is a relationship between tonsilloliths and dental plaque-related pathologies in a series of digital panoramic radiographs. MATERIALS AND METHODS: This retrospective study included digital panoramic radiographs of 859 patients admitted for routine dental examination. The panoramic images were examined for both the presence of tonsilloliths and the number of decayed, missing, restored teeth and apical periodontitis. Periodontal bone loss was also measured in thirds of optimal bone height according to the root length and a percentage of bone loss was obtained for each panoramic radiograph evaluated. RESULTS: Tonsilloliths were observed in 141 (16.4%) of all individuals. While there was no significant difference regarding the number of decayed teeth and restored teeth between tonsillolith cases (TT) and cases without tonsillolith (TC), the number of missing teeth and apical periodontitis in TT was significantly higher than TC (p: 0.004, p: 0.030, respectively). There was a significant difference between the groups in terms of the mean percentage of bone loss (p: 0.001; p < 0.05). In addition, cases showing bone loss between one-third and two-thirds of the optimal bone height in the TT group (52.5%) were significantly higher than those in TC (45.5%) (p: 0.035; p < 0.05). CONCLUSION: The relationship between dental plaque-related pathologies and tonsilloliths observed in this retrospective study should be confirmed by computed tomography studies and randomized, prospective, clinical trials conducted in a multidisciplinary manner.

Healing of periodontal suprabony defects following treatment with open flap debridement with or without an enamel matrix derivative: A randomized controlled clinical study.

OBJECTIVES: To compare the healing of suprabony defects following treatment with either open flap debridement (OFD) and application of an enamel matrix derivative (EMD) with OFD alone. METHODS: Eighty patients with suprabony periodontal defects were randomly assigned to treatment with OFD + EMD (test) or OFD alone (control). The primary outcome variable was the difference in clinical attachment level (CAL) gain. At baseline and after 12 months, full-mouth plaque scores (FMPS), full-mouth bleeding scores (FMBS), probing depths (PD), gingival recessions (GR), and CAL were recorded. RESULTS: Sixty-five patients were available for the 12-month follow-up examination. At 12 months, the mean FMPS was 21.9 ± 3.0% in the OFD + EMD and 21.1 ± 2.4% in the OFD group, respectively (p = 0.30), while mean FMBS measured 20.4 ± 3.4% in the OFD + EMD group and 19.9 ± 2.9% in the OFD group (p = 0.48). Mean CAL gain at sites treated with OFD + EMD was statistically significantly different (p = 0.0001) compared with sites treated with OFD alone (3.4 ± 0.6 mm vs 1.8 ± 0.6 mm). A statistically significant difference (p = 0.0001) was found between mean PD change in the OFD + EMD (3.9 ± 0.6 mm) and OFD alone (3.2 ± 0.6 mm) treated groups and also in terms of mean GR change between treatment with OFD + EMD (0.5 ± 0.7 mm) and OFD alone (1.4 ± 1.0 mm) (p = 0.001). CONCLUSION: Within their limits, the present results indicate that in suprabony periodontal defects, the application of EMD in conjunction with OFD may additionally improve the clinical outcomes compared with OFD alone. CLINICAL RELEVANCE: In periodontal suprabony defects, the application of EMD in conjunction with OFD may additionally enhance the clinical outcomes in terms of CAL gain and PD reduction.

Clinical and radiographic evaluation of 0.8% hyaluronic acid as an adjunct to open flap debridement in the treatment of periodontal intrabony defects: randomized controlled clinical trial.

OBJECTIVES: Present study aimed to evaluate and compare the clinical and radiographic efficacy of 0.8% hyaluronic acid (HA) gel as an adjunct to open flap debridement (OFD) versus open flap debridement (OFD) alone in the treatment of periodontal intrabony defects. MATERIALS AND METHODS: This randomized, controlled, split-mouth, clinical trial included 20 chronic periodontitis (stage II or III (grades A to B)) patients, having at least two contralateral intrabony defects. Forty bilateral intrabony defects (20 in each group) were randomly divided into test (0.8% HA gel + OFD) and control (OFD + placebo) groups. Clinical parameters evaluated at baseline, 6-months, and 12-months were plaque index (PI), gingival index (GI), probing depth (PD), clinical attachment level (CAL), and gingival recession (GR). Using cone beam computed tomography (CBCT), radiographic parameters were evaluated at baseline and 12 months. This included bone defect fill (DF), alveolar crest changes (ACC), and defect resolution (DR). CAL served as the primary outcome variable. RESULTS: After 12 months, the test group showed significantly greater CAL gain (5.1 ± 1.2 versus 4.05 ± 1.19 mm) and bone defect fill (DF) (5.67 ± 2.01 versus 4.49 ± 1.78 mm) compared to the control group. Mean PD reduction in the test group (5.3 ± 1.2 versus 4.35 ± 0.81 mm) was statistically significant compared to the control group at 12-month period. The control group showed statistically significant increase in GR (1.2 ± 0.76 versus 0.7 ± 0.73 mm) compared to the test group after 12 months. CONCLUSION: Application of hyaluronic acid gel in conjunction with open flap debridement resulted in enhanced clinical and radiographic outcomes compared to open flap debridement alone. CLINICAL RELEVANCE: Adjunctive application of HA gel in open flap debridement may improve clinical and radiographic outcomes. CLINICAL TRIAL REGISTERED NUMBER: CTRI/2018/03/012334.

Efficacy of regenerative therapy in aggressive periodontitis: a systematic review and meta-analysis of randomised controlled clinical trials.

OBJECTIVES: To analyse evidence regarding the efficacy of periodontal regenerative procedures in intrabony defects in patients treated for aggressive periodontitis (AgP). MATERIAL AND METHODS: A systematic search of the literature for randomised controlled clinical trials including patients treated for aggressive periodontitis that compared a group treated with regenerative therapy with another group treated with surgical debridement alone was conducted by two independent reviewers. RESULTS: Six studies were included in the meta-analysis of clinical and/or radiographic parameters at 6 and 12 months. Probing pocket depth was smaller at 6 months in patients treated with regenerative therapies compared with those treated with regular debridement (1.00 mm, p < 0.001, 95% CI (0.67, 1.34)). At 12 months this difference was more marked (0.41 mm, p = 0.12, 95% CI (- 0.10, 0.91)). The distance between the cemento-enamel junction and the alveolar crest at both 6 (1.36 mm, p < 0.001, 95% CI (1.03, 1.68)) and 12 months (0.90 mm, p = 0.01, 95% CI (0.24, 1.56)) was smaller in the group treated with regeneration. CONCLUSIONS: The use of biomaterials for regenerative therapy in AgP may be more effective than surgical debridement. Better outcomes were observed in terms of probing pocket depth and distance between the cemento-enamel junction and the alveolar crest at 6 months. Regeneration should be considered as a therapy to prevent tooth loss, although more studies with larger sample size and longer follow-up are needed. CLINICAL RELEVANCE: Periodontal regeneration is effective in the treatment of intrabony defects in patients with AgP, as it leads to better outcomes in clinical and radiographic parameters.

OC-STAMP promotes osteoclast fusion for pathogenic bone resorption in periodontitis via up-regulation of permissive fusogen CD9.

Cell fusion-mediated formation of multinuclear osteoclasts (OCs) plays a key role in bone resorption. It is reported that 2 unique OC-specific fusogens [ i.e., OC-stimulatory transmembrane protein (OC-STAMP) and dendritic cell-specific transmembrane protein (DC-STAMP)], and permissive fusogen CD9, are involved in OC fusion. In contrast to DC-STAMP-knockout (KO) mice, which show the osteopetrotic phenotype, OC-STAMP-KO mice show no difference in systemic bone mineral density. Nonetheless, according to the ligature-induced periodontitis model, significantly lower level of bone resorption was found in OC-STAMP-KO mice compared to WT mice. Anti-OC-STAMP-neutralizing mAb down-modulated in vitro: 1) the emergence of large multinuclear tartrate-resistant acid phosphatase-positive cells, 2) pit formation, and 3) mRNA and protein expression of CD9, but not DC-STAMP, in receptor activator of NF-κB ligand (RANKL)-stimulated OC precursor cells (OCps). While anti-DC-STAMP-mAb also down-regulated RANKL-induced osteoclastogenesis in vitro, it had no effect on CD9 expression. In our mouse model, systemic administration of anti-OC-STAMP-mAb suppressed the expression of CD9 mRNA, but not DC-STAMP mRNA, in periodontal tissue, along with diminished alveolar bone loss and reduced emergence of CD9+ OCps and tartrate-resistant acid phosphatase-positive multinuclear OCs. The present study demonstrated that OC-STAMP partners CD9 to promote periodontal bone destruction by up-regulation of fusion during osteoclastogenesis, suggesting that anti-OC-STAMP-mAb may lead to the development of a novel therapeutic regimen for periodontitis.-Ishii, T., Ruiz-Torruella, M., Ikeda, A., Shindo, S., Movila, A., Mawardi, H., Albassam, A., Kayal, R. A., Al-Dharrab, A. A., Egashira, K., Wisitrasameewong, W., Yamamoto, K., Mira, A. I., Sueishi, K., Han, X., Taubman, M. A., Miyamoto, T., Kawai, T. OC-STAMP promotes osteoclast fusion for pathogenic bone resorption in periodontitis via up-regulation of permissive fusogen CD9.

Local Application of Pyrophosphorylated Simvastatin Prevents Experimental Periodontitis.

PURPOSE: Simvastatin (SIM), a HMG-CoA reductase inhibitor widely prescribed for hypercholesterolemia, has been reported to ameliorate inflammation and promote osteogenesis. Its clinical applications on these potential secondary indications, however, have been hampered by its lack of osteotropicity and poor water solubility. To address this challenge, we propose to design and evaluate the therapeutic efficacy of a novel simvastatin prodrug with better water solubility and bone affinity. METHOD: The prodrug (SIM-PPi) was synthesized by directly conjugating a SIM trimer to a pyrophosphate (PPi). It was characterized and evaluated in vitro for its water solubility, osteotropicity, toxicity, anti-inflammatory and osteoinductive properties. It was then tested for anti-inflammatory and osteoinductive properties in vivo by three weekly injections into gingiva of a ligature-induced experimental periodontitis rat model. RESULTS: In vitro studies showed that SIM-PPi has greatly improved water-solubility of SIM and shows strong binding to hydroxyapatite (HA). In macrophage culture, SIM-PPi inhibited LPS-induced pro-inflammatory cytokines (IL-1ß, IL-6). In osteoblast culture, it was found to significantly increase alkaline phosphatase (ALP) activity with accelerated mineral deposition, confirming the osteogenic potential of SIM-PPi. When tested in vivo on an experimental periodontal bone-loss model, SIM-PPi exhibited a superior prophylactic effect compared to dose equivalent SIM in reducing inflammatory cells and in preserving alveolar bone structure, as shown in the histological and micro-CT data. CONCLUSION: SIM-PPi may have the potential to be further developed for better clinical management of bone loss associated with periodontitis.

Efficacy of metformin in the management of periodontitis: A systematic review and meta-analysis.

Periodontitis is characterized by inflammation of the periodontium and leads to loss of teeth if untreated. Although a number of surgical and pharmacological options are available for the management of periodontitis, it still affects a large proportion of population. Recently, metformin (MF), an oral hypoglycemic, has been used to treat periodontitis. The aim of this review is to systematically evaluate the efficacy of MF in the treatment of periodontitis. An electronic search was carried out using the keywords 'metformin', 'periodontal' and 'periodontitis' via the PubMed/Medline, ISI Web of Science and Google Scholar databases for relevant articles published from 1949 to 2016. The addressed focused question was: 'Is metformin effective in reducing bone loss in periodontitis? Critical review and meta-analysis were conducted of the results obtained in the selected studies. Following the removal of the duplicate results, the primary search resulted in 17 articles and seven articles were excluded based on title and abstract. Hence, 10 articles were read completely for eligibility. After exclusion of four irrelevant studies, six articles were included. The topical application of MF resulted in improved histological, clinical and radiographic outcomes. Additionally, results from the meta-analysis indicated that application of metformin improved the clinical and radiographic outcomes of scaling and root-planing, but at the same time heterogeneity was evident among the results. However, because of a lack of histological and bacterial studies, in addition to short follow-up periods and risk of bias, the long-term efficacy of MF in the treatment of bony defects is not yet ascertained. Further studies are needed to envisage the long-term efficacy of MF in the management of periodontitis.

Cyanoacrylate Adhesive as an Alternative Tool for Membrane Fixation in Guided Tissue Regeneration.

AIM: To report a well succeeded use of cyanoacrylate adhesive for fixating a resorbable membrane during a guided tissue regeneration procedure (GTR). BACKGROUND: The immobilization of membranes in GTR is essential for establishing proper environment for cell differentiation and tissue regeneration. However, some membranes are very difficult to be kept in position by sutures and its fixation by mini screws or pins may be time consuming and expensive. CASE DESCRIPTION: A 47-year-old woman presenting a vertical bone defect at the palatal aspect of the left central incisor was treated by GTR using particulate autogenous bone graft associated to a collagen membrane. The membrane was glued to the bone surrounding the defect and to the tooth surface with cyanoacrylate adhesive. The postoperative period was uneventful and 4 years later, excellent results in terms of radiographic filling of the defect and reduction of the probing depth were seen. For illustrative purposes, histological findings obtained during a previous experiment in calvaria of guinea pigs is shown, characterizing a foreign body granuloma and proving that the cyanoacrylate adhesive is a safe tool in GTR. CONCLUSION: The use of a membrane glued with cyanoacrylate to immobilize membranes in GTR is viable and safe from both technical and biological standpoints and may be advantageous for clinical and research purposes. CLINICAL SIGNIFICANCE: The alternative method for membrane fixation shown in this case report can contribute to simplify the technique in GTR procedures.

Convolutional-neural-network-based radiographs evaluation assisting in early diagnosis of the periodontal bone loss via periapical radiograph.

Background/Purpose: The preciseness of detecting periodontal bone loss is examiners dependent, and this leads to low reliability. The need for automated assistance systems on dental radiographic images has been increased. To the best of our knowledge, no studies have quantitatively and automatically staged periodontitis using dental periapical radiographs. The purpose of this study was to evaluate periodontal bone loss and periodontitis stage on dental periapical radiographs using deep convolutional neural networks (CNNs). Materials and methods: 336 periapical radiographic images (teeth: 390) between January 2017 and December 2019 were collected and de-identified. All periapical radiographic image datasets were divided into training dataset (n = 82, teeth: 123) and test dataset (n = 336, teeth: 390). For creating an optimal deep CNN algorithm model, the training datasets were directly used for the segmentation and individual tooth detection. To evaluate the diagnostic power, we calculated the degree of alveolar bone loss deviation between our proposed method and ground truth, the Pearson correlation coefficients (PCC), and the diagnostic accuracy of the proposed method in the test datasets. Results: The periodontal bone loss degree deviation between our proposed method and the ground truth drawn by the three periodontists was 6.5 %. In addition, the overall PCC value of our proposed system and the periodontists' diagnoses was 0.828 (P < 0.01). The total diagnostic accuracy of our proposed method was 72.8 %. The diagnostic accuracy was highest for stage III (97.0 %). Conclusion: This tool helps with diagnosis and prevents omission, and this may be especially helpful for inexperienced younger doctors and doctors in underdeveloped countries. It could also dramatically reduce the workload of clinicians and timely access to periodontist care for people requiring advanced periodontal treatment.

Targeted elimination of Fusobacterium nucleatum alleviates periodontitis.

Background: Fusobacterium nucleatum, a pathobiont in periodontal disease, contributes to alveolar bone destruction. We assessed the efficacy of a new targeted antimicrobial, FP-100, in eradicating F. nucleatum from the oral microbial community in vitro and in vivo and evaluated its effectiveness in reducing bone loss in a mouse periodontitis model. Methods: A multispecies bacterial community was cultured and treated with two concentrations of FP-100 over two days. Microbial profiles were examined at 24-h intervals using 16S rRNA sequencing. A ligature-induced periodontitis mouse model was employed to test FP-100 in vivo. Results: FP-100 significantly reduced Fusobacterium spp. within the in vitro community (p < 0.05) without altering microbial diversity at a 2 µM concentration. In mice, cultivable F. nucleatum was undetectable in FP-100-treated ligatures but persistent in controls. Beta diversity plots showed distinct microbial structures between treated and control mice. Alveolar bone loss was significantly reduced in the FP-100 group (p = 0.018), with concurrent decreases in gingival IL-1ß and TNF-α expression (p = 0.052 and 0.018, respectively). Conclusion: FP-100 effectively eliminates F. nucleatum from oral microbiota and significantly reduces bone loss in a mouse periodontitis model, demonstrating its potential as a targeted therapeutic agent for periodontal disease.

FP-100 eliminates F. nucleatum from an in vitro multispecies microbial community at low doses without affecting bacterial diversity. FP-100 treatment leads to the in vivo elimination of F. nucleatum, reducing alveolar bone loss and levels of pro-inflammatory cytokines in the gingiva. FP-100 is a new antimicrobial to target F. nucleatum-mediated periodontal disease.

Deep learning method to automatically diagnose periodontal bone loss and periodontitis stage in dental panoramic radiograph.

OBJECTIVES: Artificial intelligence (AI) could be used as an automatically diagnosis method for dental disease due to its accuracy and efficiency. This research proposed a novel convolutional neural network (CNN)-based deep learning (DL) ensemble model for tooth position detection, tooth outline segmentation, tooth tissue segmentation, periodontal bone loss and periodontitis stage prediction using dental panoramic radiographs. METHODS: The dental panoramic radiographs of 320 patients during the period January 2020 to December 2023 were collected in our dataset. All images were de-identified without private information. In total, 8462 teeth were included. The algorithms that DL ensemble model adopted include YOLOv8, Mask R-CNN, and TransUNet. The prediction results of DL method were compared with diagnosis of periodontists. RESULTS: The periodontal bone loss degree deviation between the DL method and ground truth drawn by the three periodontists was 5.28%. The overall PCC value of the DL method and the periodontists' diagnoses was 0.832 (P <​ 0.001). ​The ICC value was 0.806 (P <​ 0.001). The total diagnostic accuracy of the DL method was 89.45%. CONCLUSIONS: The proposed DL ensemble model in this study shows high accuracy and efficiency in radiographic detection and a valuable adjunct to periodontal diagnosis. The method has strong potential to enhance clinical professional performance and build more efficient dental health services. CLINICAL SIGNIFICANCE: The DL method not only could help dentists for rapid and accurate auxiliary diagnosis and prevent medical negligence, but also could be used as a useful learning resource for inexperienced dentists and dental students.

Dental radiographic changes in individuals with COVID-19: a controlled retrospective study.

OBJECTIVE: The aim of this study is to compare the pre-COVID-19 and post-COVID-19 dental radiological findings of individuals with positive rRT-PCR test results and with healthy controls using the apical periodontitis grade scale (APGS), radiographic-based periodontal bone loss (R-PBL), and radiographic DMFT indices, and to investigate the relatively long-term dental effects of COVID-19. METHODS: This study included people who had two panoramic radiographs taken between 2018 and 2022. There are 52 patients with positive rRT-PCR tests in the study group. The control group included 50 individuals. Study and control groups were compared using the apical periodontitis grade scale (APGS), radiographic-based periodontal bone loss (R-PBL), and radiographic DMFT indices. RESULTS: Although results showed a significant difference in percentage R-PBL value and R-PBL types in the study group, there was no significant difference in percentage R-PBL value and R-PBL types in the control group. Also, both groups showed a significant difference in the DMFT index. CONCLUSIONS: According to the results of this study, it can be said that COVID-19 increases the incidence of periodontitis, and it can be interpreted that the pandemic may adversely affect the general oral health of all people.